1. Field of the Invention
This invention relates, in general, to cable connectors and, more specifically, to tap assemblies for connection to energized high-voltage concentric cables.
2. Description of the Prior Art
Cable connectors for high-voltage concentric electrical cables are used to connect a lead or "tapping" cable to the high-voltage "tapped" cable. Normally, such connectors are associated with underground electrical power distribution systems and are applied to the primary cable usually for the purpose of connecting a transformer to the primary cable.
Because of the high voltages involved and because of the insulation systems required for underground operation, the arrangement of a "hot" tap connector which is to be applied to the tapped cable while is is energized must be specifically constructed for this type of application. Cable taps designed for connection to non-energized cables or to cables energized with a relatively low voltage are not suitable for tapping energized high-voltage electrical cables because the required preparation and tap adjustments cannot be made safely when the cable is energized.
The tapping operation of energized electrical cables requires the use of long insulated tools to provide a large safety margin for the workmen. Usually, these are awkward to work with and some particular operations are practically impossible to perform at the end of a "hotstick." Therefore, it is desirable, and it is an object of this invention, to provide a cable tap connector which may be installed with a minimum of work involving long insulated tools.
Many prior art cable taps for non-energized cables require removal of the insulation around the center conductor before the cable tap can be connected. Other prior art arrangements do not require removal of the insulation but pierce the insulation and the center conductor. Piercing the center conductor can damage the center conductor and may fail to provide the necessary pressure between the center conductor and the piercing member. A few prior art connectors, such as that disclosed in U.S. Pat. No. 3,380,014, substantially pierce the insulation but not the center conductor. While the apparatus disclosed in the referenced patent is much different than that of the present invention, the basic principle of piercing the insulation without substantially piercing the conductor within the insulation is highly desirable for use in tapping high-voltage concentric energized cables. Therefore, it is also desirable, and it is another object of this invention, to provide a cable tap which is suitable for use in tapping energized high-voltage concentric cables without piercing the center conductor of the cable.